<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>定位的拓展</title>
    <style>
        .f{
            position: relative;
            background-color: gray;
            height: 200px;
            width: 290px;
        }
        .s{
            background-color: red;
            position: relative;
        }
    </style>
</head>
<body>
    <!-- 当给行内元素设置绝对和固定定位布局时，可为其设置长和宽 -->
    <!-- 当给块级元素设置布局时不设置长和宽则会默认大小 -->
    <!-- 浮动不会遮挡文字，定位会 -->
    <span class="f">AAAAAAAAAAAAAA</span>
    <div class="s">sadasd</div>
</body>
</html>